Service quality in P2P streaming systems

Relying on end users to contribute bandwidth to the system peer-to-peer (P2P) overlays provide a cheap and scalable way to distribute live video content in the Internet. However, being inherently dynamic due to peers joining and leaving the system at arbitrary time and running over the best-effort Internet, successful commercial usage of these systems may suffer from unstable media quality provided to end users. In this survey, we consider problems related to providing quality of media delivery in P2P streaming systems. We show that in spite of numerous systems available today no one incorporates mechanisms capable to maintain a certain level of quality of delivered media. We identify reasons behind that and discuss possible solutions to this problem. (C) 2011 Elsevier Inc. All rights reserved.